Their Little Sister
by DeanObsession
Summary: Dean and Sam got a new sister, John took her in and they couldnt stay away from this beautiful little girl. They have dreams and touch her hair, they both want her and she encourages it. They feel more for their sister. D/OC S/OC D/OC/S sis!fic
1. A new sister

A New Sister

She flew at him, teeth bared and her sharp canines showing. John lurched out of the way at the last second and turned with his silver machete in position. He watched the reckless female carefully. She was beautiful, her dark wavy hair framing her neck and shoulders, and an almost flawless angular face. Her dark red lips stretched bright against her pale skin as she smiled carnivorously at him. Her eyes were dark from hunger as she lunged at him again. He gripped the machete tighter and swung forward, ignoring the loud cry she let out as it cut through skin and bone. The machete broke free from her neck and her body and head tumbled to the floor in twain.

Breathing in the air thick with the smell of blood, John walked through the house, looking for other vampires that may have nested along with this one. The house was fairly new and built for a small family. He walked down the hallway upstairs with the polished wood flooring. He opened a door into a pink room. Looking around, he saw a crib and stiffened. He edged towards it, expecting the worst.

He looked into the crib and found a small child wrapped in a thin pink blanket. She was breathing and asleep, her cheeks filled with color. She was just a human, as far as he could tell. He noticed the windows were covered neatly with thick cardboard to keep sunlight out. He pulled back the blanket and saw red marks on her neck and arms, vampire bites. They were clean and healing, as if she was being taken care of. He turned on a lamp on the side table and glanced at the picture next to it. It showed the vampire holding the young girl, both smiling. The mother was turned recently, he thought. He picked the small girl up, holding her sleeping form in his arms. He found a car seat in the closet and went downstairs and outside to the impala.

Walking into the motel with a small girl on his arm, John introduced her to 9 year old Sam and 14 year old Dean.

"Dad, is she a monster?" Sam asked cautiously as he stepped towards their father.

"No, Sammy," He answered. "But her mother was. She was turned into a vampire and this young girl, Kelsey, was left behind."

"How do you know she's not one?" He asked.

"Dad would've done the tests, Sam." Dean said. He got up from the bed and walked over to their dad, standing next to Sam. They were both starring at the small girl who was glancing at them from his jacket with wide blue eyes.

"How old is she?" Dean asked. He put his hand on hers, her eyes drawing him in.

"Kelsey is three." John said. Kelsey clung to his jacket, her head on his chest. He pulled out a piece of paper he had pulled from a scrapbook in her room before Sam could ask how he knew. He handed it to Sam and rubbed her back. Dean removed his hand from hers as the two boys read the paper.

"Kelsey Marie Carson. She was born three years ago." Dean said. Sam caught Kelsey's eye, he starred at her beautiful face as she smiled at him and smiled back.

"Dean, hold her while I go get her stuff." John ordered. Dean held out his arms and was surprised at how warm the small body in his arms was. He held her while she clung to his neck. His thin black t-shirt felt like nothing as her body pressed to his. She smelled nice, he thought. John carried in a folded crib and a small bag of things.

"She's your new sister, boys." He said to them. Neither objected, both of them already loved this girl.

Both boys loved the sparkle of Kelsey's eyes and the smile she would give them. It seemed like flirting, even though she was so young, but as she turned five, then seven, and at nine she still had them, they were hers to love and be loved by.


	2. Sister or lover

Sister or lover

When Kelsey was nine she was finally old enough to carry a weapon when they went out. She was turning into more of a hunter by each passing day. Her blue eyes held emotion like any other child's would, only she felt different than most little sisters would. She loved the way Sammy held her and the way Dean would kiss her forehead. The things they did subconsciously were things she liked. She wanted Sam, but she also wanted Dean. Who was to say she couldn't have them both. They were more than her brothers, she loved them and they knew they belonged to her.

Dean had started looking at with a different feeling, something that he's always felt, but it was growing stronger around her. He would only see her and when he would be with other girls he would think of her as would cum. Imagining her sweet lips and smooth soft skin beneath him. To save money, John simply had Kelsey sleep with Sam. Sam was fifteen and still shared a bed with Kelsey, but he felt her small form pushing against him one night and grabbed her, his arm around her, pulling her towards him. He breathed in the smell of her brown curls and ran his hand under her thin pink nightgown. He froze when she moved. She had always wanted to be close to him, but he wanted more. He shouldn't be doing this, but he wanted to.

"Sammy." She moaned in her sleep. He moved his hand slowly down her body, feeling how warm she was before he had to pull away. He knew it was wrong, but he wanted her. He groaned at the feel of her body as she tried to get closer to him. She turned around to face him.

"Sammy, it's ok." She said. He had pulled away sharply when she had turned over, but those words were what he needed to hear and he leaned forward and kissed her hungrily. He grabbed her waist roughly and ground against her.

"Kels." He groaned. She rocked into him along with his movements. He was hard and she felt good against him, he couldn't stop. He lifted her nightgown and pushed against her naked back and underwear. He pulled his pants down, leaving his boxers and her underwear the only barrier left. She moaned and he came within his boxers.

"I'm sorry, Kels."He held her in his arms before going to the bathroom to change. He got out of the bathroom and got into bed beside her again. He ran his hand softly through her curls and thought about how wrong what he did was. She wanted it to, or maybe she was talking about something else. He couldn't believe he went that far, just to touch her and to get off with her beside him instead of imagining her while he was in the shower. She was his sister, but she could also be a lover.


	3. I dream of you

I dream of you

The next night, Sam leaned away from Kelsey as they slept. He didn't want to make another move, he wanted her too badly that he would give in within seconds of smelling or feeling her the right way. Dean, in the other bed, didn't know about last night and Sam wasn't about to confess to him about his dirty deed.

Dean was asleep, but he thought of Kelsey as he became aroused. He opened his eyes and turned over and faced her in bed. He could see her small form beneath the sheets she shared with Sam, who was facing the other way. He stroked himself while he imagined her, being with him and wanting him. He closed his eyes and thought of all the things he could do to her. He smirked when he realized she would've liked every one of them if it happened. He jumped out of bed and strode over to the bathroom, taking a shower would help him get over this need for the night.

He turned on the water and stripped his clothes off before getting in. Letting his body soak in the hot water, steam rose around him as he washed his hair and stroked his cock. When the soap was gone, he continued rubbing himself and didn't notice when the bathroom door opened or when the small girl undressed herself and opened the shower curtain.

"Kelsey." She startled him as she got into the shower with him. He dropped his hand from his erect cock and starred at her small, naked body as she stood there before him. He wanted to grab her body and slam her against the shower wall and fuck her brains out.

She stepped towards him and walked under the falling water. The hot water cascaded down her face, her breasts and further down her stomach. He swallowed, his mouth suddenly dry. She got closer and he could now feel her breath on his lips as she leaned in. He grabbed her waist and pulled her against him. Her breasts were pressed against his lower chest and his cock was between her legs, rubbing against her clit. She moaned and he leaned down to kiss her. She held onto him as he felt every inch of her skin with his hands and kissed her with his lips and tongue. She pulled away and smiled at him.

She knelt down and her face was right in front of his cock. He looked down at her in astonishment as she pulled him into her mouth and began sucking. She moved her hand along the remaining exposed cock as she bobbed her head up and down on his length. He grabbed her hair and pulled her closer, shoving his cock down her throat as he bucked his hips forward and thrusted into her mouth.

"Yes Kelsey." He groaned. She smiled against his cock and continued to bob her head, taking as much as she could into her mouth. He pounded into her mouth faster and harder and pushed her face closer.

"Almost there baby!" He said as he pounded into her, his body shuddering with pleasure. He came in her mouth, his seed shooting down her throat and she swallowed happily. She pulled away after she sucked him dry. He pulled her up and held her in his arms as the water fell on them. That was so much better than a wet dream.


	4. We share her

We share her

Sam and Dean didn't share with each other what they did. Instead as the years went by, they looked at each other and how they both looked at Kelsey. They both knew that they shared her. She didn't belong to just one of them and they both assumed that she had her moments with them. She thought of them as special moments, every time they were close it proved how much they love her. Her beautiful brown hair grew longer and her body fuller as she turned fifteen and they felt more of a need for her than ever.

Sam was twenty-one years old and John still hadn't assumed anything about what both of his boys wanted to do with his daughter. She had grown cleverer with how she got their attention. Sam and Dean tried to pull away, they knew more now than ever that what they were doing was wrong, it was beyond wrong. She would climb into bed with Dean while he was sleeping and he would grab her waist in his sleep and wake up holding her still. Sam would go shopping with her and she would try short skirts on and have him tell her which one looked best. In the car, when John went in the stores or hunters houses, she would grab one of them through their pants and make them groan loudly. They couldn't control how much they wanted to get her naked, to rip the clothes off her body and take her.

They didn't talk about her with each other, unless one of them had stayed behind with her at the motel during a hunt and they were checking up on how she was doing. Dean caught Sam walking by her room numerous times one night and he pulled him aside and yelled at him that what they were doing was wrong and dangerous. If John ever found out, they would be in so much trouble. Three weeks later, John had been close to catching the yellow eyed demon, but he was too close, and he was killed. He died saving Dean's life, with a deal. Dean kept to himself and walked around and acted like an asshole for a month before Kelsey was able to distract him and get them some time alone together.

They were staying at Bobby's after that. Dean and Bobby had left on a hunt for a few days when Sam grew impatient with his little sister. Sam walked slowly down the hallway, his head in a book, reading up on demons. He stumbled into Kelsey as she walked out of the bathroom. He felt steam rush in his face and he looked up. Kelsey fixed the towel around her as she looked up into his face.

"Sorry Sammy. You should watch where you're going." She said with a wink and turned around to walk to her room. She left the door ajar with the light on and he couldn't help but walk down the hall and look inside. She had just gotten her clothes out of the drawer as he reached the door and looked inside. She dropped her towel on the floor and he let go of his book. He fumbled to pick it up in the air before it hit the ground.

He looked up again as he stood and watched her pull a tank top over her perky breasts and lean stomach. She pulled on panties and comfortable pants before picking the towel up and walking towards the door. He moved away from the door and strode down the hall, stopping outside his door to run a hand through his hair and breathe slowly. He watched her walk out her door and downstairs, throwing the towel in the basket on the way down. He made a quick decision to drop the book on his bed and make his way downstairs.

She saw him come downstairs from the corner of her eye as she flipped through the channels while comfortably sitting on her legs on the couch, leaning on the armrest. She smirked as he walked over and sat down on the right side of the couch, spreading his legs and leaning on the other armrest. His jeans and flannel shirt made him look even cuter than usual. She wondered if she should tease him, they had only ever gone so far. She wanted more, with both of them, but there was something about Sam that made her want more of him. With Dean, she could seduce him into any game she wanted to play. She had been on her knees and he on his with each other many times before and she could never get enough. They would grab each other and feel each other's skin beneath each other, but neither of them would take that next step with her. Sam had been so close to doing more than touching her and kissing her, but he stopped.

She leaned over and rested her head on his shoulder as they watched some scary movie on TV.

"Sam, what were you reading earlier?" Kelsey asked casually.

"Something on demons, their coming and we need to be fully equipped for what they will bring." He answered after a pause.

"That's cool." She said. They continued watching TV for a few minutes before she spoke again. "Sam, I want you." She looked up into his eyes and he glanced at her before turning to face her.

"What?" He asked in disbelief.

"I want you, Sam Winchester. I want everything about you." She said as she sat on her knees on the couch and faced him. "I want to be with you, I want your lips and your skin and I want you to hold me, to love me."

"I do love you, Kelsey." He said with a sigh.

"Do you love me enough to want to be with me, to freely kiss me without having to hide in the hall so Dean or Dad doesn't see? He does the same thing Sam. You and Dean hide like its bad to want it."

"Because it is. We shouldn't do any of it with you, it's not right." Sam said.

"It's right to me, Sam. You do it still, I know you want me and you say you love me, but how long will it take you to pull away and want those other girls I always see Dean with."

"They're not you, Kels. I wouldn't want them." He said frustrated.

"Do you love me enough to sleep with me?" Sam was silent. It seemed that he stayed that way for hours. As she turned away to leave, she was near tears. All of a sudden he pulled her arm back and pulled her in for a long and hard kiss. He fought his tongue with hers as he pulled her body to his. She pulled at his shirt as he held her face and body. He helped her unbutton his shirt as he lifted hers over her head and continued kissing her passionately. Sam pulled away and rested his forehead against hers.

"Kelsey, you sure about this?" She ran her hands through his hair and kissed him.

"Yes, I'm sure." She ran her hands down his chest and abs. He felt her breasts and kissed down her neck. Sam picked her up and walked her to his bedroom, kissing her the whole way up. He laid her down on the bed and pulled down her pants as he went above her. She was left in her panties as he kissed her down her stomach. She unbuttoned his pants and pulled them down to his ankles, he kicked them the rest of the way off and ran his hands down her smooth stomach. She was warm and soft and he savored the way she felt and the way she breathed his name. Pulling down his boxers, he looked into her eyes before touching her through her panties. She moaned and leaned her head against the pillow lightly as she closed her eyes. She squirmed beneath him as he put two, then three fingers inside of her and thrust deeper into her.

He pulled out and pulled her panties down her legs and threw them on the floor. He leaned over her, his erect cock brushing against her clit.

"I really want you to be ready for this. I have been, for so long." He said.

"I am." He thrust into her all the way as they stared into each other's eyes.

"Oh god, Sam!" She cried out. He slowly thrust in and out of her. She began to move her hips with his and they had a rhythm that they kept to, kissing and moving with each other. He moved faster and deeper as she moaned. She dug her nails into his back as he moved in and out. They moved together, the rhythm of their bodies moving as one. He loved the feel of her around him and he could finally hold her and do what he wanted with her, no restrictions. No matter how wrong it was, it felt right and that was all that mattered in that moment.


End file.
